Tire vulcanizer and method for assembling tire vulcanizer

ABSTRACT

A tire vulcanizer is disclosed including a sector arranged with respect to a side plate with a high degree of positioning accuracy. The tire vulcanizer includes: the sector that shapes a tread of a tire; a segment to which the sector is fixed and causes the sector to move in a tire radial direction; a bolt that fixes the sector to the segment; a ring-shaped jacket ring provided on an outer side in the tire radial direction of the segment; paired upper and lower side plates that shape sidewalls of the tire; and mold parting surfaces defined by the sector and the paired upper and lower side plates. Mold inner ends of the mold parting surfaces are arranged on the tread, and the mold parting surfaces extend outward in the tire radial direction from the mold inner ends.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a tire vulcanizer and a method forassembling the tire vulcanizer.

2. Description of the Related Art

A tire is manufactured by building an unvulcanized green tire andvulcanizing and shaping the green tire in a specified shape by using atire vulcanizer.

The tire vulcanizer that includes: a vulcanizing mold that shapes thegreen tire in the specified shape; and a drive mechanism that drives thevulcanizing mold and is referred to as a container has been known. Thevulcanizing mold that includes: a sector that shapes a tread of thetire; and paired upper and lower side plates that shape sidewalls of thetire has been known.

In this tire vulcanizer, the green tire is set onto the lower sideplatein a mold open state where the upper sideplate and the sector areseparated from the lower side plate. Thereafter, the drive mechanismlowers the upper side plate and causes the sector to move inward in atire radial direction. In this way, the upper side plate and the sectorcome close to the lower side plate, and the vulcanizing mold is broughtinto a mold closed state. Here, the sector is divided into plural piecesin a circumferential direction. The pieces of the sector are radiallyseparated in the mold open state, and gather to have a ring shape in themold closed state.

A pattern having various projected and recessed shapes is provided on anouter surface of each of the tread and the sidewalls. In recent years,in order to improve the tire design, there is a case where the projectedand recessed shapes are continuously provided from the tread to each ofthe sidewalls. In the case where such a pattern is provided and wheremold inner ends (a parting line) of mold parting surfaces that aredefined by the sector and each of the side plates are arranged on ashoulder, rubber that spills out of the mold parting surfaces possiblyremains in a conspicuous portion in external appearance, or theprojected and recessed shapes, which continue from the tread to each ofthe sidewalls, possibly deviate in the circumferential direction in theconspicuous portion.

To handle such a problem, it has conventionally been proposed that themold parting surfaces defined by the sector and each of the side platesare configured as surfaces that are parallel with the tire radialdirection or surfaces that are obliquely inclined with respect to thetire radial direction and that the mold inner ends of the mold partingsurfaces are arranged on the tread.

Patent Document: JP-A-2001-96538

However, a problem as described below occurs in the tire vulcanizer thatis opened/closed by moving the sector in the tire radial direction inthe case where the mold parting surfaces defined by the sector and eachof the side plates are configured as the surfaces that are parallel withthe tire radial direction or the surfaces that are obliquely inclinedwith respect to the tire radial direction. In the tire vulcanizer inwhich the mold parting surfaces are configured as the surfaces that areparallel with the tire radial direction, in the case where a distancebetween the mold parting surfaces of the sector and each of the sideplates is short, the sector and each of the side plates rub against eachother to cause wear when the sector moves in the radial direction.Meanwhile, in the case where the distance between the mold partingsurfaces of the sector and each of the side plates is long, the rubberis likely to spill out of the mold parting surfaces during vulcanizationmolding, which leads to shaping failure of a spill. That is, in order toprevent the rubber spill while suppressing the sector and each of theside plates from rubbing against each other to cause the wear, a highdegree of accuracy is demanded for a position of the sector with respectto each of the side plates.

In addition, the tire vulcanizer, in which the mold parting surfaces areconfigured as the surfaces that are obliquely inclined with respect tothe tire radial direction, is brought into a taper-fitted state duringclosing of the mold. In the taper-fitted state, the sector and each ofthe side plates come into contact with each other on the inclinedsurfaces. Accordingly, also in such a tire vulcanizer, in order to bringthe mold parting surfaces into tight contact with each other whilesuppressing the sector and each of the side plates from rubbing againsteach other to cause the wear resulted from the movement of the sector inthe tire radial direction, the high degree of the accuracy is demandedfor the position of the sector with respect to each of the side plates.

The sector is divided into the plural pieces in the circumferentialdirection and is connected to the mechanism that causes movement of thesector in a vertical direction and the tire radial direction. Thus, itis not easy to manage an attachment position of each member constitutingthe tire vulcanizer such that all of the sectors are arranged at desiredpositions during closing of the mold. As a result, the positions of thesectors with respect to each of the side plates are likely to deviatefrom each other.

The present invention has been made in view of the above point andtherefore has a purpose of providing a tire vulcanizer and a method forassembling the tire vulcanizer capable of adjusting positions of sectorssuch that all of the sectors are arranged at desired positions duringclosing of a mold and capable of arranging the sectors with respect toside plates with a high degree of positioning accuracy.

SUMMARY OF THE INVENTION

A tire vulcanizer according to the present invention is a tirevulcanizer that shapes and vulcanizes a tire, and includes: a sectorthat shapes a tread of the tire and is divided in a tire circumferentialdirection; a segment, to which the sector is fixed, and which causes thesector to move in a tire radial direction; a bolt that is inserted in abolt hole from an outer side in the tire radial direction so as to fixthe sector to the segment, the bolt hole penetrating the segment in thetire radial direction; a ring-shaped jacket ring that is provided on anouter side in the tire radial direction of the segment; paired upper andlower side plates that shape sidewalls of the tire; and mold partingsurfaces that are defined by the sector and the paired upper and lowerside plates. Mold inner ends of the mold parting surfaces are arrangedon the tread, and the mold parting surfaces extend outward in the tireradial direction from the mold inner ends. The segment is provided suchthat a fixing position of the sector can be adjusted in a verticaldirection. The jacket ring has: a through hole that penetrates thejacket ring in the tire radial direction; and a tapered surface as aninner circumferential surface that extends outward in the tire radialdirection as advancing downward. When the jacket ring moves downwardwith respect to the segment so as to cover an outer side in the tireradial direction of the segment, the segment moves inward in the tireradial direction, the adjacent sectors in the tire circumferentialdirection tightly contact each other, and the through hole communicatewith the bolt hole.

In a preferred aspect of the present invention, the mold partingsurfaces may be provided in parallel with the tire radial direction. Inanother preferred aspect of the present invention, the tire vulcanizermay include a sealing member that closes the through hole.

In yet another preferred aspect of the present invention, the tirevulcanizer may include paired upper and lower attachment plates that arerespectively fixed to the paired upper and lower side plates and supportthe segment in a manner to allow sliding of the segment. The segment mayinclude paired upper and lower sliding surfaces that respectively slideon the paired upper and lower attachment plates. The paired upper andlower sliding surfaces may be inclined such that outer sides in the tireradial direction thereof are directed toward a central portion in a tirewidth direction. When the segment causes the sector to move outward inthe tire radial direction, the paired upper and lower sliding surfacesmay respectively slide on the paired upper and lower attachment plates,and a distance between the mold parting surfaces may be increased. Inthis case, an angle of each of the paired upper and lower slidingsurfaces with respect to the tire radial direction is preferably equalto or larger than 5° and equal to or smaller than 10°. Also, in thiscase, the paired upper and lower sliding surfaces are preferably flatsurfaces.

A method for assembling a tire vulcanizer according to the presentinvention is a method for assembling a tire vulcanizer that includes: asector that shapes a tread of the tire and is divided in a tirecircumferential direction; a segment, to which the sector is fixed, andwhich causes the sector to move in a tire radial direction; a bolt thatis inserted in a bolt hole from an outer side in the tire radialdirection so as to fix the sector to the segment, the bolt holepenetrating the segment in the tire radial direction; a ring-shapedjacket ring that is provided on an outer side in the tire radialdirection of the segment; paired upper and lower side plates that shapesidewalls of the tire; paired upper and lower attachment plates that arerespectively fixed to the paired upper and lower side plates and supportthe segment in a manner to allow sliding of the segment; and moldparting surfaces that are defined by the sector and the paired upper andlower side plates, in which mold inner ends of the mold parting surfacesare arranged on the tread, and the mold parting surfaces extendingoutward in the tire radial direction from the mold inner ends, in whichthe segment is provided such that a fixing position of the sector can beadjusted in a vertical direction, and in which the jacket ring has: athrough hole that penetrates the jacket ring in the tire radialdirection; and a tapered surface as an inner circumferential surfacethat extends outward in the tire radial direction as advancing downward,and moves downward with respect to the segment to cover an outer side inthe tire radial direction of the segment, so as to make the segment moveinward in the tire radial direction, to make the adjacent sectors in thetire circumferential direction tightly contact each other, and to makethe through hole communicate with the bolt hole. The method forassembling a tire vulcanizer includes: temporarily fixing the sector tothe segment by the bolt; supporting the segment, to which the sector istemporarily fixed, on paired upper and lower attachment plates that arerespectively fixed to the paired upper and lower side plates; andadjusting a vertical position of the sector with respect to the segmentin a state where the jacket ring covers an outer side in the tire radialdirection of the segment and makes the adjacent sectors in the tirecircumferential direction tightly contact each other, and screwing thebolt to fix the sector to the segment.

In the tire vulcanizer according to the present invention, in a moldclosed state where the adjacent sectors in the tire circumferentialdirection tightly contact each other, the bolt can be screwed to fix thesector to the segment after the distance between the mold partingsurfaces defined by the sector and the side plate is adjusted.Accordingly, the positions of the sectors can be adjusted such that allthe sectors are located at the desired positions when the mold isclosed. Therefore, the sectors can be arranged with respect to the sideplates with a high degree of positioning accuracy.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a half cross-sectional view of a state during vulcanizationmolding by a tire vulcanizer according to an embodiment.

FIG. 2 is a half cross-sectional view of a stage at which a diameter ofa sector in the tire vulcanizer is increased.

FIG. 3 is an enlarged view of a main section in FIG. 2.

FIG. 4 is another enlarged view of the main section in FIG. 2.

FIG. 5 is a half cross-sectional view of a stage at which an increase inthe diameter of the sector in the tire vulcanizer is completed.

FIG. 6 is a half cross-sectional view of a stage at which the sector inthe tire vulcanizer is lifted.

FIG. 7 is a plan view of a state where the plural sectors are fixed to aholding jig.

FIG. 8 is a plan view of a state where the sectors are temporarily fixedto a segment.

FIG. 9 is a half cross-sectional view of the tire vulcanizer during anassembly and depicts a state where an upper attachment plate and a lowerattachment plate support the segment, to which the sector is temporarilyfixed.

FIG. 10 is a half cross-sectional view of the tire vulcanizer during theassembly and depicts a state where a through hole of a jacket ringcommunicates with a bolt hole of the segment.

FIG. 11 is a half cross-sectional view of a tire vulcanizer according toa modified embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A description will hereinafter be made on embodiments of the presentinvention with reference to the drawings.

As depicted in FIG. 1, a tire vulcanizer includes: a vulcanizing mold10; a container 20 to which the vulcanizing mold 10 is attached; firstlifting/lowering means 50 and second lifting/lowering means 51 thatlift/lower the vulcanizing mold 10 and the container 20; and a bladder60. In the tire vulcanizer, an unvulcanized green tire is set such thata tire axial direction (a tire width direction) is vertically arranged.Then, the tire vulcanizer vulcanizes and shapes the unvulcanized greentire in a specified shape by heating and pressurization.

The vulcanizing mold 10 is a shaping mold that includes: an upper andlower pair of an upper side plate 11 and a lower side plate 12; pluralsectors 13 that are divided in a circumferential direction; and an upperand lower pair of bead rings 14, 15, and that shapes an outer surface (adesign surface) of a tire T.

As a material of the vulcanizing mold 10, a metallic material such asaluminum, an aluminum alloy, or iron can be selected. However, iron ispreferably selected due to low thermal expansion at a vulcanizingtemperature. All of the paired upper and lower side plates 11, 12, theplural sectors 13, and the paired upper and lower bead rings 14, 15,which constitute the vulcanizing mold 10, are preferably made of iron sothat a distance between mold parting surfaces generated in thevulcanizing mold 10 can easily be set to a desired distance at thevulcanizing temperature.

The sector 13 is a mold that shapes a tread 1 of the tire T. The sector13 is divided into plural units (for example, nine units) in a tirecircumferential direction, and the plural units are provided such thateach thereof can be displaced in a manner to increase/reduce a diameterin a tire radiation direction (a tire radial direction). In a moldclosed state where each of the sectors 13 is arranged at a mold closedposition, the adjacent sectors 13 in the tire circumferential directiongather to have a ring shape.

The upper side plate 11 is a mold that shapes a sidewall 2 and a bead 3arranged in an upper portion of the tire T. The lower side plate 12 is amold that shapes the sidewall 2 and the bead 3 arranged in a lowerportion of the tire T. The bead rings 14, 15 are provided on inner sidesin the tire radial direction of the upper and lower pair of the upperside plate 11 and the lower side plate 12. The bead rings 14, 15 areconfigured such that the beads 3 of the tire T can be fitted thereto.

The vulcanizing mold 10 is provided with the mold parting surfaces, oneach of which the mold is divided in the tire width direction, that is,mold parting surfaces 16 defined by the sector 13 and the upper sideplate 11 and mold parting surfaces 17 defined by the sector 13 and thelower side plate 12. The mold parting surfaces 16, 17, which are definedby the sector 13 and the upper and lower pair of the upper side plate 11and the lower side plate 12, are provided in parallel with the tireradial direction that is a moving direction of the sector 13. In themold parting surfaces 16, 17, mold inner ends 16 a, 17 a referred to asparting lines are located on the tread 1 of the tire T.

The sector 13 includes an upper flange section 13 a and a lower flangesection 13 b. The upper flange section 13 a is projected upward from themold parting surface 16 defined between the sector 13 and the upper sideplate 11. The lower flange section 13 b is projected downward from themold parting surface 17 defined between the sector 13 and the lower sideplate 12. In the mold closed state where the adjacent sectors 13 in thetire circumferential direction tightly contact each other, the upperflange section 13 a abuts an end surface 11 b on an outer side in thetire radial direction that is provided in the upper side plate 11, andthe lower flange section 13 b abuts an end surface 12 b on the outerside in the tire radial direction that is provided in the lower sideplate 12.

Projected positions of the upper flange section 13 a and the lowerflange section 13 b on the mold parting surfaces 16, 17 are preferablyset such that, before the upper and lower pair of the upper flangesection 13 a and the lower flange section 13 b come into contact withthe upper and lower pair of the upper side plate 11 and the lower sideplate 12, the adjacent sectors 13 in the tire circumferential directioncome into contact with each other, and thereafter the upper flangesection 13 a and the lower flange section 13 b respectively come intocontact with the upper side plate 11 and the lower side plate 12.

As an example, the projected positions of the upper flange section 13 aand the lower flange section 13 b can be set such that each of adistance between the upper flange section 13 a and the upper side plate11 and a distance between the lower flange section 13 b and the lowerside plate 12 is 0.03 mm to 0.2 mm when the adjacent sectors 13 in thetire circumferential direction come into contact with each other.

Either one of the upper flange section 13 a and the end surface 11 b ofthe upper side plate 11, which opposes the upper flange section 13 a inthe tire radial direction, (in this example, the upper flange section 13a) is provided with a first projection pin 18 that is projected towardthe other (in this example, the end surface 11 b of the upper side plate11), and the other is provided with a first recessed section 19 intowhich the first projection pin 18 is fitted in the mold closed state ofthe tire vulcanizer.

Similarly, either one of the lower flange section 13 b and the endsurface 12 b of the lower sideplate 12, which opposes the lower flangesection 13 b in the tire radial direction, (in this example, the lowerflange section 13 b) is provided with the first projection pin 18 thatis projected toward the other (in this example, the end surface 12 b ofthe lower side plate 12), and the other is provided with the firstrecessed section 19 into which the first projection pin 18 is fitted inthe mold closed state of the tire vulcanizer.

The at least one first projection pin 18, which is provided in each ofthe upper flange section 13 a and the lower flange section 13 b, isprovided for each of the plural sectors 13. In this example, the firstprojection pin 18 is provided in a central portion in the tirecircumferential direction of each of the upper flange section 13 a andthe lower flange section 13 b.

The first projection pins 18 are fitted into the first recessed sections19 when the vulcanizing mold 10 is closed. In this way, each of thefirst recessed sections 19 adjusts a relative position in the tirecircumferential direction between the sector 13 and corresponding one ofthe upper and lower pair of the upper side plate 11 and the lower sideplate 12, and thereby positions the sector 13.

The first projection pin 18 may be provided on each of the end surface11 b of the upper side plate 11 and the end surface 12 b of the lowerside plate 12, and the first recessed section 19 may be provided in eachof the upper flange section 13 a and the lower flange section 13 b.

The sector 13 is provided with a bolt hole 16 b for fixing a holding jig70, which will be described later, to the mold parting surfaces 16defined between the sector 13 and the upper side plate 11 (see FIG. 7).

In the vulcanizing mold 10, a main groove shaping rib (not depicted) anda lateral groove shaping rib 13 c are provided in the sector 13. Themain groove shaping rib is a rib for shaping a main groove that extendsin the tire circumferential direction in the tread 1. The lateral grooveshaping rib 13 c is a rib for shaping a lateral groove 4 that extends inthe tire width direction in the tread 1. In the vulcanizing mold 10,recessed section shaping ribs 11 a, 12 a are respectively provided onthe upper side plate 11 and the lower side plate 12. Each of therecessed section shaping ribs 11 a, 12 a is a rib for shaping a recessedsection 5 in the sidewall 2 in a continuous manner with the lateralgroove 4 in the tread 1.

In such a vulcanizing mold 10, a vent hole, which is not depicted and isopened to the inside of the mold, is provided in each of the sector 13and the upper and lower pair of the upper side plate 11 and the lowerside plate 12. Each of the vent holes is connected to a suction unitsuch as a vacuum pump via an air release tube. The suction unit releasesair in the mold from the vent hole during vulcanization molding. In thisway, accumulation of the air, which possibly results in a hole inrubber, is prevented.

The container 20 includes: plural segments 21, each of which holds thesector 13; a jacket ring 22 that causes the segments 21 to move in thetire radial direction; an upper attachment plate 23 that supports theupper side plate 11 and the upper bead ring 14 and is arranged on anupper side of the segments 21; and a lower attachment plate 24 thatsupports the lower side plate 12 and the lower bead ring 15 and isarranged on a lower side of the segments 21.

On an outer side of the sector 13 in the tire radial direction, thesegment 21 is provided for each of the divided sectors 13 (see FIG. 8).On an inner side of the segment 21 in the tire radial direction, anattachment surface 21 a is provided to come into surface contact withthe outer side of the sector 13 in the tire radial direction. Theattachment surface 21 a is a vertical surface that is perpendicular to ahorizontal direction, and the sector 13 moves along the attachmentsurface 21 a. In this way, an attachment position of the sector 13 canbe changed in the vertical direction.

The segment 21 is provided with a bolt hole 25 that penetrates thesegment 21 in the tire radial direction. The sector 13 is fixed to theattachment surface 21 a of the segment 21 by a bolt 26 that is insertedin the bolt hole 25 from the outer side in the tire radial direction. Avertical length of the bolt hole 25, which is provided in the segment21, is set to be longer than a diameter of a shaft portion of the bolt26 by a specified length. In this way, even in the case where theattachment position of the sector 13 deviates in the vertical directionwith respect to the attachment surface 21 a, the sector 13 is fixed bythe bolt 26.

On an upper surface of the segment 21, an upper sliding surface 27 isinclined such that an outer side in the tire radial direction thereof isdirected toward a central portion (that is, downward) in the tire widthdirection. The upper sliding surface 27 slides on an upper slide 28 thatis provided in the upper attachment plate 23.

On a lower surface of the segment 21, a lower sliding surface 29 isinclined such that an outer side in the tire radial direction thereof isdirected toward the central portion (that is, upward) in the tire widthdirection. The lower sliding surface 29 slides on a lower slide 30 thatis provided in the lower attachment plate 24.

An inclination angle of each of the upper sliding surface 27 and thelower sliding surface 29 provided in the segment 21 is not particularlylimited but is preferably equal to or larger than 5° and equal to orsmaller than 10° with respect to the tire radial direction. In addition,the upper sliding surface 27 and the lower sliding surface 29 providedin the segment 21 are preferably flat surfaces that are not bent, andrespectively slide on the upper slide 28 and the lower slide 30 insurface contact states.

Furthermore, in the segment 21, a lateral surface on an opposite side(the outer side in the tire radial direction) from a lateral surface towhich the sector 13 is attached is an inclined surface 31 that isinclined outward in the tire radial direction as advancing downward.

The jacket ring 22 is a ring-shaped member that is provided on aradially outer side of the plural segments 21. The jacket ring 22 isprovided with through holes 36, each of which corresponds to the bolthole 25 provided in the segment 21 and penetrates the jacket ring 22 inthe tire radial direction. Each of the through holes 36 is closed in anairtight state by a sealing member 37 that is attachable/detachableto/from the jacket ring 22.

An inner circumferential surface of the jacket ring 22 is a taperedsurface 22 a that is inclined along the inclined surface 31 provided onthe outer side in the tire radial direction of the segment 21. Thetapered surface 22 a provided in the jacket ring 22 is slidably coupledto the inclined surface 31 of the segment 21. In a state of beingseparated upward from the lower attachment plate 24, the jacket ring 22supports the segment 21 (see FIG. 6). In addition, as depicted in FIGS.1, 2, and 5, in a state where the segment 21 is placed on the lowerslide 30 of the lower attachment plate 24, the jacket ring 22 is liftedor lowered relative to the segment 21. In this way, while sliding on theinclined surface 31 provided in the segment 21, the jacket ring 22causes the segment 21 to move in the tire radial direction. As a result,the sector 13, which is held by the segment 21, is configured to allowdisplacement thereof in the manner increase/reduce a diameter in thetire radial direction.

When the jacket ring 22 is lowered to a position of covering the entireouter side in the tire radial direction of the segment 21, the tirevulcanizer is brought into the mold closed state where the adjacentsectors 13 in the circumferential direction tightly contact each other.In this state, each of the through holes 36 provided in the jacket ring22 communicates with the bolt hole 25 provided in the segment 21. Inthis way, in the mold closed state of the tire vulcanizer, the bolt 26,which fixes the sector 13 to the segment 21, can be attached/detached.

The upper side plate 11 and the upper slide 28 are fixed to a lowersurface of the upper attachment plate 23 by a bolt, which is notdepicted.

Either one of the upper side plate 11 and the upper attachment plate 23(in this example, the upper attachment plate 23) is provided with asecond projection pin 32 that has a tapered shape and is projectedtoward the other (in this example, the upper side plate 11), and theother is provided with a second recessed section 33 into which thesecond projection pin 32 is fitted. The second recessed section 33 has aconical shape that corresponds to the shape of the second projection pin32 and is narrowed toward a bottom. When the second projection pin 32 isfitted into the second recessed section 33, a relative position betweenthe upper side plate 11 and the upper attachment plate 23 is adjusted,and the upper side plate 11 is thereby positioned. The second projectionpin 32 may be provided in the upper side plate 11, and the secondrecessed section 33 may be provided in the upper attachment plate 23.

The upper slide 28 is arranged at a position that is on the outer sidein the tire radial direction of the upper side plate 11 and that opposesthe upper sliding surface 27, which is provided on the upper surface ofthe segment 21. The segment 21 is coupled to the upper slide 28 in aslidable manner in the tire radial direction. As depicted in FIG. 6, theupper slide 28 supports the segment 21 in the state of being separatedupward from the lower attachment plate 24, and guides the movement ofthe segment 21 during the movement of the segment 21 in the tire radialdirection.

The lower side plate 12 and the lower slide 30 are fixed to an uppersurface of the lower attachment plate 24 by a bolt, which is notdepicted.

Either one of the lower side plate 12 and the lower attachment plate 24(in this example, the lower attachment plate 24) is provided with asecond projection pin 34 that has a tapered shape and is projectedtoward the other (in this example, the lower side plate 12), and theother is provided with a second recessed section 35 into which thesecond projection pin 34 is fitted. The second recessed section 35 has aconical shape that corresponds to the shape of the second projection pin34 and is narrowed toward a bottom. When the second projection pin 34 isfitted into the second recessed section 35, a relative position betweenthe lower side plate 12 and the lower attachment plate 24 is adjusted,and the lower side plate 12 is thereby positioned. The second projectionpin 34 may be provided in the lower sideplate 12, and the secondrecessed section 35 may be provided in the lower attachment plate 24.

The lower slide 30 is arranged at a position that is on the outer sidein the tire radial direction of the lower side plate 12 and that opposesthe lower sliding surface 29, which is provided on the lower surface ofthe segment 21. The lower slide 30 supports the segment 21 in a mannerto allow sliding thereof in the tire radial direction, and guides themovement of the segment 21 during the movement of the segment 21 in thetire radial direction.

A heater, which is not depicted, is provided in the lower attachmentplate 24, the jacket ring 22, and the like. The heater is configured toinclude a heating medium and a pipe through which the heating mediumflows, and heats the entire vulcanizing mold 10.

The first lifting/lowering means 50 lifts/lowers the upper attachmentplate 23 relative to the lower attachment plate 24. The secondlifting/lowering means 51 lifts/lowers the jacket ring 22 separatelyfrom the segment 21 supported by the upper attachment plate 23.

The bladder 60 is formed of an expandable or contractable rubberresilient body in a toroidal shape in which a central portion in theaxial direction is swollen outward. The bladder 60 is arranged on aninner surface side of the green tire, is inflated when being suppliedwith pressurized gas (for example, steam or nitrogen gas), andpressurizes the green tire from the inner side. An upper end and a lowerend as both ends of the bladder 60 in the axial direction are supportedby an extension/contraction support section 61. The bladder 60 isconfigured to supply/discharge the pressurized gas to/from the insidevia a fluid port, which is not depicted. The extension/contractionsupport section 61 is a member that supports the bladder 60 in a mannerto allow extension/contraction of a distance between the upper end andthe lower end of the bladder 60. The extension/contraction supportsection 61 includes: an upper cramp ring 62 that fixes the upper end ofthe bladder 60; a lower cramp ring 63 that fixes the lower end of thebladder 60; and an extendable/contractable shaft section 64 that can beextended/contracted.

Next, a description will be made on a method for assembling the tirevulcanizer by attaching the vulcanizing mold 10 to the container 20.

Initially, as depicted in FIG. 7, the plural sectors 13 are aligned inthe circumferential direction such that a mold surface shaping the tread1 of the tire T faces inward. In this embodiment, the lower flangesection 13 b, which is projected downward from the mold parting surface17 constituting the lower surface of the sector 13, is provided. Thus,the sector 13 cannot stand upright by itself. In such a case, asdepicted in FIG. 7, the plural sectors 13, which are aligned in thecircumferential direction, are fixed to the ring-shaped holding jig 70by bolts 71 so as to maintain this state.

Next, the jacket ring 22, to which the segments 21 are attached, islowered from the upper side of the plural sectors 13, which are alignedin the circumferential direction. Then, the segment 21 is arranged onthe outer side in the tire radial direction of each of the sectors 13.Thereafter, as depicted in FIG. 8, the bolt 26 is inserted in the bolthole 25 provided in the inclined surface 31 of each of the segments 21so as to temporarily fix each of the sectors 13 to the respectivesegment 21. The holding jig 70, which is attached to the sector 13, isdetached. In FIG. 8, the jacket ring 22 is not depicted.

Next, the segment 21, to which the sector 13 is temporarily fixed, iscoupled to the upper slide 28, which is provided on the upper attachmentplate 23, in the slidable manner in the tire radial direction. Inaddition, the segment 21, to which the sector 13 is temporarily fixed,is lowered from the upper side of the lower attachment plate 24, towhich the lower side plate 12 and the lower slide 30 are fixed. Thelower sliding surface 29 of the segment 21 is placed on the lower slide30, and the segment 21 is thereby supported by the lower slide 30. Notethat, immediately after the lower sliding surface 29 of the segment 21is placed on the lower slide 30, as depicted in FIG. 9, the segment 21is located at a lower end of the jacket ring 22 due to own weight. Thus,the sector 13, which is fixed to the segment 21, is located away fromthe upper side plate 11 and the lower side plate 12 in the tire radialdirection.

Next, as depicted in FIG. 10, the jacket ring 22 is lowered to theposition of covering the entire outer side in the tire radial directionof the segment 21 and causes the segment 21 to move inward in the tireradial direction until the tire vulcanizer is brought into the moldclosed state (until the adjacent sectors 13 in the circumferentialdirection tightly contact each other).

Next, in the mold closed state, the bolt 26, which fixes the sector 13to the segment 21, is loosened from the through hole 36 provided in thejacket ring 22. Thereafter, the vertical attachment position of thesector 13 with respect to the segment 21 is adjusted such that thesector 13 comes into contact with the upper side plate 11 and the lowerside plate 12.

When the adjustment of the vertical attachment position of the sector 13with respect to the segment 21 is completed, the bolt 26 is screwedagain from the through hole 36 so as to fix the sector 13 to the segment21. Then, the sealing member 37 is attached to the through hole 36, andthe assembly of the tire vulcanizer is completed.

In this embodiment, the description has been made on the case where thesector 13 moves inward in the tire radial direction until the tirevulcanizer is brought into the mold closed state, and the bolt 26 isthen loosened to adjust the vertical attachment position of the sector13. However, the vertical attachment position may be regulated by thefollowing method.

For example, when the sector 13 is temporarily fixed to the segment 21by the bolt 26, the sector 13 can move in the vertical direction byreceiving an external force. At this time, the segment 13 is fixed tothe segment 21 with such intensity of a fastening force that preventsdetachment of the sector 13 from the segment 21 and rattling of thesector 13. Thereafter, the jacket ring 22 is lowered to the position ofcovering the entire outer side in the tire radial direction of thesegment 21 and causes the segment 21 to move inward in the tire radialdirection until the tire vulcanizer is brought into the mold closedstate. At the time, the sector 13 is fixed to the segment 21 such thatthe sector 13 can move in the vertical direction by receiving theexternal force. Thus, the sector 13 is pressed in the vertical directionby the upper side plate 11 and the lower side plate 12 and is arrangedat a position where the mold parting surfaces 16, 17 of the sector 13respectively contact the upper side plate 11 and the lower side plate12. Then, in this state, the bolt 26 is further screwed from the throughhole 36 provided in the jacket ring 22. In this way, the sector 13 maybe fixed to the segment 21.

Alternatively, the bolt 26 is loosened immediately after the tirevulcanizer is brought into the mold closed state. Then, the verticalposition of the sector 13 is adjusted such that each of the distancebetween the sector 13 and the mold parting surface 16 of the upper sideplate 11 and a distance between the sector 13 and the mold partingsurface 17 of the lower sideplate 12 falls within a specified range.Thereafter, the bolt 26 may be screwed to fix the sector 13 to thesegment 21.

The green tire is vulcanized and shaped by using the tire vulcanizerhaving the configuration that has been described so far. In this way, apneumatic tire is manufactured.

In detail, the green tire that has been built by a known method is setin the vulcanizing mold 10 of the tire vulcanizer in the mold openstate. After the bladder 60 is attached to the inner surface side of thegreen tire, the vulcanizing mold 10 is brought into the mold closedstate as depicted in FIG. 1.

In order to shift the vulcanizing mold 10 from the mold open state tothe mold closed state, the first lifting/lowering means 50 lowers theupper side plate 11, which is provided on the upper attachment plate 23,and the segment 21, and the second lifting/lowering means 51 lowers thejacket ring 22 and the segment 21 attached thereto.

A speed at which the first lifting/lowering means 50 lowers the upperside plate 11 and the segment 21 is set to be equal to a speed at whichthe second lifting/lowering means 51 lowers the jacket ring 22 and thesegment 21. Accordingly, the segments 21 and the sectors 13 do not movein the tire radial direction. The upper side plate 11, the sectors 13,the segments 21, and the jacket ring 22 move downward and come close tothe lower side plate 12, which is provided on the lower attachment plate24.

Then, when the lower sliding surface 29 of the segment 21 is placed onthe lower slide 30 of the lower attachment plate 24, the secondlifting/lowering means 51 further lowers the jacket ring 22. In thisway, the lower sliding surface 29 slides on the lower slide 30 of thelower attachment plate 24, the upper sliding surface 27 slides on theupper slide 28 of the upper attachment plate 23, and the segment 21thereby moves inward in the tire radial direction. The upper slidingsurface 27 and the lower sliding surface 29 provided in the segment 21are inclined such that the outer sides in the tire radial directionthereof are directed toward the central portion in the tire widthdirection. Accordingly, when the sector 13 moves inward in the tireradial direction with the segment 21, the upper side plate 11 is loweredby the inclination of the upper sliding surface 27, and the segment 21and the sector 13 are lowered by the inclination of the lower slidingsurface 29. That is, in conjunction with the inward movement of thesegment 21 and the sector 13 in the tire radial direction, the distancebetween the mold parting surfaces 16 defined by the sector 13 and theupper side plate 11 is gradually reduced, and the distance between themold parting surfaces 17 defined by the sector 13 and the lower sideplate 12 is gradually reduced.

Then, the segment 21 and the sector 13 move inward in the tire radialdirection by a specified amount. At this time, the adjacent sectors 13in the tire circumferential direction come into contact with each otherbefore the upper and lower pair of the upper flange section 13 a and thelower flange section 13 b comes into contact with the upper and lowerpair of the upper side plate 11 and the lower side plate 12.

After the adjacent sectors 13 in the tire circumferential directioncontact each other, the sectors 13 further move inward in the tireradial direction and reach the mold closed positions where the adjacentsectors 13 in the tire circumferential direction tightly contact eachother. When each of the sectors 13 reaches the mold closed position, theupper flange section 13 a and the lower flange section 13 b respectivelycontact the upper sideplate 11 and the lower side plate 12. In this way,the further inward movement of the sector 13 in the tire radialdirection is restricted, and the sector 13 no longer moves inward in thetire radial direction from the mold closed position (the position wherethe adjacent sectors 13 in the tire circumferential direction tightlycontact each other).

In addition, the vertical position of the sector 13 is adjusted duringthe assembly of the tire vulcanizer. Accordingly, in a state where thesector 13 has reached the mold closed position, the mold partingsurfaces 16, 17 defined by the sector 13, the upper side plate 11, andthe lower side plate 12 tightly contact each other, and the vulcanizingmold 10 is brought into the mold closed state as depicted in FIG. 1.

Note that, when the sector 13 moves inward in the tire radial directionto the mold closed position as described above, the first projectionpins 18 provided in the upper flange section 13 a and the lower flangesection 13 b are fitted into the first recessed sections 19 provided inthe end surface 11 b of the upper side plate 11 and the end surface 12 bof the lower side plate 12, and thereby position the sector 13 in thetire circumferential direction with respect to the upper side plate 11and the lower side plate 12.

After the vulcanizing mold 10 is closed as described above, the bladder60 is supplied with the pressurizing gas and is inflated. In this way,the green tire is pressurized and heated between the vulcanizing mold 10and the bladder 60, and such a state is maintained for a specifiedperiod. As a result, the tire T is vulcanized and shaped.

After the green tire is vulcanized, the vulcanizing mold 10 is broughtinto the mold open state, and a taking-out process to take out thevulcanized tire T from the tire vulcanizer is performed.

In order to shift the vulcanizing mold 10 from the mold closed state tothe mold open state, initially, the second lifting/lowering means 51lifts the jacket ring 22 and causes the sector 13, which is held by thesegment 21, to move outward in the tire radial direction. In this way,the diameter of the sector 13 is increased. At this time, the firstlifting/lowering means 50 is stopped. However, when the upper attachmentplate 23 and the lower attachment plate 24 are applied with the externalforce in the vertical direction, the upper attachment plate 23 movesupward by such an external force.

As described above, in the tire vulcanizer of this embodiment, the uppersliding surface 27 and the lower sliding surface 29 provided in thesegment 21 are inclined such that the outer sides in the tire radialdirection thereof are directed toward the central portion in the tirewidth direction. Accordingly, when the segment 21 moves outward in thetire radial direction as depicted in FIG. 2, the upper sliding surface27 slides outward in the tire radial direction on the upper slide 28 ofthe upper attachment plate 23 while pressing the upper attachment plate23 upward, and the lower sliding surface 29 slides outward in the tireradial direction on the lower slide 30 of the lower attachment plate 24while pressing the lower attachment plate 24 downward.

The upper attachment plate 23, which is pressed upward by the uppersliding surface 27, moves upward with respect to the segment 21.Accordingly, when the segment 21 starts moving radially outward, asdepicted in FIG. 3, the upper side plate 11, which is fixed to the upperattachment plate 23, also moves upward with respect to the segment 21,and the distance between the mold parting surfaces 16 defined by thesector 13 and the upper side plate 11 is increased.

In addition, the lower attachment plate 24, which is pressed downward bythe lower sliding surface 29, moves downward with respect to the segment21. Accordingly, when the segment 21 starts moving radially outward, asdepicted in FIG. 4, the lower side plate 12, which is fixed to the lowerattachment plate 24, also moves downward with respect to the segment 21,and the distance between the mold parting surfaces 17 defined by thesector 13 and the lower side plate 12 is increased. Note that, in thecase where the lower attachment plate 24 is fixed and where the segment21 starts moving radially outward, the segment 21 moves upward, and thedistance between the mold parting surfaces 17 defined by the sector 13and the lower side plate 12 is increased.

Then, after the increase in the diameter of the sector is completed asdepicted in FIG. 5, the first lifting/lowering means 50 is lifted. Inthis way, as depicted in FIG. 6, the upper side plate 11, which isprovided on the upper attachment plate 23, and the sector 13 are lifted.That is, the upper side plate 11 and the sector 13 are separated fromthe lower side plate 12, and a mold opening operation of the upper sideplate 11 and the lower side plate 12 is thereby performed. Thereafter,the vulcanized tire T is taken out from the tire vulcanizer in the moldopen state. Note that, while the upper sideplate 11 and the sector 13move upward, the jacket ring 22 is lifted in a synchronized manner withthe upper side plate 11 by the second lifting/lowering means 51, so asto maintain the increased diameter state of the sector 13.

In the tire vulcanizer of this embodiment, the attachment position ofthe sector 13 to the segment 21 can be changed in the verticaldirection. In addition, in the mold closed state where the adjacentsectors 13 in the circumferential direction tightly contact each other,the through hole 36 provided in the jacket ring 22 communicates with thebolt hole 25 provided in the segment 21, and the bolt 26 can thereby bescrewed/unscrewed. Thus, the vertical attachment position of the sector13 with respect to the segment 21 can easily be adjusted such that eachof the distances between the mold parting surfaces 16, 17 defined by thesector 13, the upper and lower pair of the upper side plate 11 and thelower side plate 12 becomes the desired distance.

In this embodiment, the through hole 36 provided in the jacket ring 22is closed in the airtight state by the sealing member 37. Thus, theinternal pressure of the mold is easily reduced by the suction unitduring vulcanization molding, and the accumulation of the air, whichpossibly results in the hole in the rubber, is less likely to occur.

In the tire vulcanizer of this embodiment, the upper sliding surface 27and the lower sliding surface 29, which respectively slide on the upperattachment plate 23 and the lower attachment plate 24, are inclined suchthat the outer sides in the tire radial direction thereof are directedtoward the central portion in the tire width direction. Accordingly,when the segment 21 moves inward in the tire radial direction, thedistances between the mold parting surfaces 16, 17 are graduallyreduced. Meanwhile, when the segment 21 moves outward in the tire radialdirection, the distances between the mold parting surfaces 16, 17 aregradually increased. That is, when the sector 13 is located at the moldclosed position, the mold parting surfaces 16, 17 defined by the sector13, the upper side plate 11, and the lower side plate 12 tightly contacteach other. Meanwhile, when the sector 13 is located outward in the tireradial direction from the mold closed position, clearances are generatedbetween the mold parting surfaces 16, 17. Accordingly, even when thetire vulcanizer is repeatedly opened/closed, the mold parting surfaces16, 17 do not rub against each other. Therefore, durability of the tirevulcanizer can be improved.

In addition, immediately after the segment 21 starts moving radiallyoutward, the upper side plate 11 moves with the upper attachment plate23 in a direction away from the tire T that has been vulcanized andshaped. Thus, the tire T can easily be taken out from the vulcanizingmold 10.

In the tire vulcanizer of this embodiment, in the case where the uppersliding surface 27 and the lower sliding surface 29 provided in thesegment 21 are the flat surfaces that slide on the upper slide 28 andthe lower slide 30 in the surface contact states, the segment 21 canmove with a high degree of positioning accuracy without rattling, andthus displacement of the sector 13 in the mold closed state can besuppressed.

Modified Embodiment

A description will be made on a modified embodiment of the presentinvention with reference to FIG. 11. Note that the same components asthose in the above embodiment will be denoted by the same referencesigns, and the detailed description thereon will not made.

In the above embodiment, the description has been made on the case wherethe mold parting surfaces 16, 17 defined by the sector 13, the upperside plate 11, and the lower side plate 12 are parallel with the tireradial direction. However, the present invention is not limited to sucha case, and the mold parting surfaces only have to extend outward in thetire radial direction from the mold inner ends thereof arranged on thetread 1 of the tire T.

For example, as depicted in FIG. 11, in a tire vulcanizer of thismodified embodiment, mold parting surfaces 160, 170 defined by thesector 13, the upper side plate 11, and the lower side plate 12 areobliquely inclined with respect to the tire radial direction such thatinner sides in the tire radial direction thereof (that is, sides of moldinner ends 160 a, 170 a) are directed toward the central portion in thetire width direction.

Also, in such a tire vulcanizer, similar operational effects to those inthe above embodiment are exerted. Note that the rest of theconfiguration of the modified embodiment is the same as theconfiguration in the above embodiment, and thus the detailed descriptionthereon will not be made.

The embodiments that have been described so far are merely provided asexamples and thus have no intention to limit the scope of the invention.These novel embodiments can be implemented in any of various otheraspects, and various types of elimination, replacement, and changes canbe made thereto within the scope that does not depart from the gist ofthe invention.

What is claimed is:
 1. A tire vulcanizer that vulcanizes and shapes atire, the tire vulcanizer comprising: a sector that shapes a tread ofthe tire and is divided in a tire circumferential direction; a segment,to which the sector is fixed, and which causes the sector to move in atire radial direction; a bolt that is inserted in a bolt hole from anouter side in the tire radial direction so as to fix the sector to thesegment, the bolt hole penetrating the segment in the tire radialdirection; a ring-shaped jacket ring that is provided on an outer sidein the tire radial direction of the segment; paired upper and lower sideplates that shape sidewalls of the tire; and mold parting surfaces thatare defined by the sector and the paired upper and lower side plates,wherein mold inner ends of the mold parting surfaces are arranged on thetread, and the mold parting surfaces extend outward in the tire radialdirection from the mold inner ends, the segment is provided such that afixing position of the sector can be adjusted in a vertical direction,and the jacket ring has: a through hole that penetrates the jacket ringin the tire radial direction; and a tapered surface as an innercircumferential surface that extends outward in the tire radialdirection as advancing downward, and moves downward with respect to thesegment to cover an outer side in the tire radial direction of thesegment, so as to make the segment move inward in the tire radialdirection, to make the adjacent sectors in the tire circumferentialdirection tightly contact each other, and to make the through holecommunicate with the bolt hole.
 2. The tire vulcanizer according toclaim 1, wherein the mold parting surfaces are provided in parallel withthe tire radial direction.
 3. The tire vulcanizer according to claim 1further comprising: a sealing member that closes the through hole. 4.The tire vulcanizer according to claim 1 further comprising: pairedupper and lower attachment plates that are respectively fixed to thepaired upper and lower side plates and support the segment in a mannerto allow sliding of the segment, wherein the segment includes pairedupper and lower sliding surfaces that respectively slide on the pairedupper and lower attachment plates, the paired upper and lower slidingsurfaces are inclined such that outer sides in the tire radial directionthereof are directed toward a central portion in a tire width direction,and when the segment causes the sector to move outward in the tireradial direction, the paired upper and lower sliding surfacesrespectively slide on the paired upper and lower attachment plates, anda distance between the mold parting surfaces is increased.
 5. The tirevulcanizer according to claim 4, wherein an angle of each of the pairedupper and lower sliding surfaces with respect to the tire radialdirection is equal to or larger than 5° and equal to or smaller than10°.
 6. The tire vulcanizer according to claim 4, wherein the pairedupper and lower sliding surfaces are flat surfaces.
 7. A method forassembling a tire vulcanizer that shapes and vulcanizes a tire, the tirevulcanizer including: a sector that shapes a tread of the tire and isdivided in a tire circumferential direction; a segment, to which thesector is fixed, and which causes the sector to move in a tire radialdirection; a bolt that is inserted in a bolt hole from an outer side inthe tire radial direction so as to fix the sector to the segment, thebolt hole penetrating the segment in the tire radial direction; aring-shaped jacket ring that is provided on an outer side in the tireradial direction of the segment; paired upper and lower side plates thatshape sidewalls of the tire; paired upper and lower attachment platesthat are respectively fixed to the paired upper and lower side platesand support the segment in a manner to allow sliding of the segment; andmold parting surfaces that are defined by the sector and the pairedupper and lower side plates, mold inner ends of the mold partingsurfaces being arranged on the tread, and the mold parting surfacesextending outward in the tire radial direction from the mold inner ends,the segment being provided such that a fixing position of the sector canbe adjusted in a vertical direction, and the jacket ring having: athrough hole that penetrates the jacket ring in the tire radialdirection; and a tapered surface as an inner circumferential surfacethat extends outward in the tire radial direction as advancing downward,and moving downward with respect to the segment to cover an outer sidein the tire radial direction of the segment, so as to make the segmentmove inward in the tire radial direction, to make the adjacent sectorsin the tire circumferential direction tightly contact each other, and tomake the through hole communicate with the bolt hole, the method forassembling a tire vulcanizer comprising: temporarily fixing the sectorto the segment by the bolt; supporting the segment, to which the sectoris temporarily fixed, on paired upper and lower attachment plates thatare respectively fixed to the paired upper and lower side plates; andadjusting a vertical position of the sector with respect to the segmentin a state where the jacket ring covers an outer side in the tire radialdirection of the segment and makes the adjacent sectors in the tirecircumferential direction tightly contact each other, and screwing thebolt to fix the sector to the segment.